Advances in wireless technology and the proliferation of portable electronic devices have sparked an increasing demand for anytime, anywhere connectivity. Consumers today have come to expect immediate access to news and financial data, regardless of where they are. Many people, whether or not they are actively trading stock, wish to follow the movement of stock and/or commodity prices. News broadcasts on television often feature an electronic ticker tape at the bottom of the screen. Many popular websites and electronic-financial companies, such as E*Trade, display stock price movement in real time because there is a strong demand for this information. For this reason certain small portable electronic devices, such as portable digital assistants and wristwatches are utilized for tracking stock movement. These devices can display stock prices and denote price fluctuations in a very compact form factor. Price fluctuations are commonly represented as up or down arrows. The drawback with these small devices, and wristwatches in particular, is that the viewable display area is so small that it is difficult to discern the direction of the arrows. Additionally, someone who is keenly interested in a stock's price movement would also need to know the magnitude of the change in addition to the direction of the change. This information, displayed in text format, would be too difficult to read on a watch face because of its small size.
FIG. 1 shows a portable display device 100 worn as a wristwatch. The display area 101 represents the typical dimensions of a display area on a wrist watch. As can be clearly seen, the display area is quite small, typically about 16.5 mm by 22 mm. While this size is adequate for displaying a clock face, it presents a problem when more information and a combination of text and graphics needs to be conveyed in the same small space. Additionally, the increasing popularity of “smart watches” has created a need for data entry and selection capabilities for wrist watches. This need has been addressed in commonly-owned U.S. Pat. No. 6,525,997 B 1 “EFFICIENT USE OF DISPLAY REAL ESTATE IN A WRIST WATCH DISPLAY” incorporated by reference as if fully set forth herein. A rotating wheel, or “jog encoder” 105 allows a user to scroll over and select options by rotating and depressing the wheel, respectively. The display area 101 can also be a touch-sensitive high resolution display screen which displays not only the time, but can also present icons to be selected by a user by depressing the zone on the screen where the icon is located.
In addition to stock prices, there are other types of variable data which an individual might wish to keep track of, such as location/compass indicators from a Global Positional System (GPS), ambient temperature and barometric pressure. The problem is that any meaningful data concerning changes in these values are difficult to view on very small displays, using current technology. Therefore there is a need for a device which overcomes the shortcomings of the prior art.